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The aim of this study was to compare local and commonly available cultivars of lucerne in Latvian market for forage and seed production in the conditions of Latvia. The trials were conducted at the Institute of Agriculture in Skriveri (56°37 N and 25°07 E), the Latvia University of Agriculture (LLU), in the time period of 2014-2015. The results showed that there were no wintering problems for any lucerne cultivars included in our trials during favourable winter without lasting black frosts and rapid temperature fluctuations. If winter conditions were favourable, significantly higher dry matter yields (DMY) in the 1st year of use were provided by faster-growing cultivars: 'Gea' (10.98 t ha-1) and 'Eugenia' (11.13 t ha-1) in total in four cuts; as well as 'Malvina' (10.77 t ha-1), 'Birute' (10.50 t ha-1) and 'SK Rasa' (10.11 t ha-1) in total in three cuts. However, during unfavorable wintering conditions in the winter of 2014, significant damages for cultivars with the southern origin were observed. During two years higher and hence more stable dry matter yields on average were provided by the varieties: 'Malvina', 'Birute' and 'SK Rasa'. Lucerne cultivars of the southern origin had better regrowth intensity, they could provide additional mowing in the growing season, but in unfavourable conditions their wintering may be risky, especially in the north-east of Latvia. Under favorable climatic conditions lucerne varieties with self-pollinating properties provide high seed yields, i.e., more than 600 kg ha-1. Better results in our trials in terms of seed production were achieved by the varieties: 'Jogeva 118'; 'SK Rasa' and 'Skriveru'. [ABSTRACT FROM AUTHOR]

Breeding of perennial legumes and initial seed production have been carried out at the Research Institute of Agriculture in Skriveri for nearly 70 years. Eight red clover varieties, two varieties of alsike clover and two varieties of alfalfa have been developed. The varieties are included in the perennial grass seed mixtures and widely used in formation of highly productive meadows and pasture swards. They are characterized by different longevity, ripening time, productivity level, number of sward cuttings per season. There are both diploid and tetraploid varieties, which are suitable for different forage production ways. These varieties are included in the European Common Catalogue of plant varieties and they are grown and multiplied in seed production fields in European countries and Canada. [ABSTRACT FROM AUTHOR]

In recent years, perennial grasses have not been considered only as a forage crop but focus has shifted to their usage as an energy crop. Special interest has been caused by reed canary grass, which is widely spread in natural biocenosis. The scientific expeditions have been organized and all regions of Latvia have been explored to gather material and information about biodiversity of perennial species of wild grasses. Several natural populations of reed canary grass (Phalaris arundinacea L.) were collected under different soil and climate conditions. The accessions were of different quality in many respects depending on collection site. Samples taken from the marshy meadows on lakeshore of the Lake Lubana were coming into flowers unevenly over a longer period of time and formed a little number of culms, whereas samples collected on the banks of the River Daugava were earlier and formed considerably more culms and were coming into flowers evenly over a shorter period of time. Breeding on reed canary grass in Latvia has not been done previously. Attention to the wild populations of RCG usually has been focused on their feeding value. Though, these populations have a good potential for selection of a new varieties intended for varied purposes. The field trials with ten wild accessions of RCG were established, and winter hardiness, growth intensity and various phenological observations were evaluated. After a comprehensive evaluation of the wild populations by important economic and morphologic characteristics, some valuable samples were found. The population 'Brigena' proved such valuable characteristics as good winter hardiness, high dry matter yields, and intensive development of productive culms. In recent years, consumption of reed canary grass as energy feedstock has increased rapidly in Latvia. It is grown by farmers in all regions and the total planted area has exceeded 800 ha. Mostly are grown varieties 'Marathon' (USA) and 'Bamse' (Sweden). DM yields obtained by farmers in Latvia on average are 6 - 9 t ha-1. Further research has to be continued. [ABSTRACT FROM AUTHOR]

The papilionaceous plants have a high value of biomass, they are the excellent source of proteins and an indispensable part of improving the soil with nitrogen, in particular it is important in ecological agriculture. The expanding of those plants sowing area nowadays is a prior task of agriculture in many European countries, including Latvia. Trifolium family include more than 300 species. In Latvia mainly used in agriculture is red clover (Trifolium pratense L.), where most of red clover sowing area (meadows and pasture) is covered with diploid (2n=14) varieties. But in last year's more importance is paid to tertraploid varieties (4n=28) breeding. The aim of red clover breeding program is offering varieties with high adaptation potential - able to grow in various types of soil, better photosynthesis activity for more competitiveness with weeds and higher biomass and seeds harvest, winter-hardy, long-term, durable against sicknesses and pests. Historically (since the 60 years of the last century) the main red clover breeding method is the free intervarietal hybridization and following individual and mass selection. For obtaining of tetraploid breeding source material the most common method is the chromosome number doubling using colchicine. In result of cooperation between LLU Research Institute of Agriculture, and Latvia Plant Genetics laboratory of Institute of Biology (University of Latvia) the group of biotechnology methods for enhancing of tetraploid red clover breeding source material obtaining was elaborated. The in vitro method for chromosome doubling of plantlets and in vitro cultivation of the tetraploid plantlets were developed. For ploidy determination the BD FACSJazz cell sorter with the flow cytometer function was used. The high percentage of cells with different ploidy plantlets after incubation in colchicine were found. The influence of genotype were observed on tetraploid cell development and plantlets surviving after colchicine treatment. 176 plantlets with well-developed roots in 2-3 leaves stage were planted in soil and grown in a greenhouse for about a month, then replanted in the soil in field conditions and grown till the maturity. After the evaluation 30 plants were chosen for including in further breeding program. In the next progeny of red clover 60% of stable tetraploid plants were establish. [ABSTRACT FROM AUTHOR]